<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>hover</title>
    <style>
        .box{
            width: 260px;
            background-color: #0043d3;
            color: white;
            height: 260px;
            text-align: center;
            font-size: 86px;
        }
        .box:hover{background-color: #ec7ab0}
    </style>
</head>
<body>
    <div class="box">
        我会变背景色
    </div>

</body>
</html>